Apparatus for making up fabric pieces of a predetermined length generally on sewing machines

ABSTRACT

An apparatus for producing preselected lengths of sewn fabric of the type used for belt loops on trousers or for entire belts in which sensing means and related circuitry are provided to detect and provide for elimination of defective material with the minimum amount of waste.

United States Patent 1 91 111 1 3,799,088

Marforio Mar. 26, 1974 APPARATUS FOR MAKING UP FABRIC [56] References Cited PIECES OF A PREDETERMINED LENGTH UNITED STATES PATENTS GENERALLY ON SEWING MACHINES 3,487,798 l/l928 Marforio 112/1212? Inventor: Nerino Marforio, Milan, Italy S.p.A. Virginio Rimoldi & C., Milan, Italy Filed: Sept. 14, 1972 Appl. No.: 288,953

Assignee:

Foreign Application Priority Data Sept. 21, 1971 Italy 28861/71 US. Cl. 112/130 Int. Cl D05b 37/04 Field of Search 112/130, 129, I22, 252,

ll2/l2l.27, 121.26, 121.11, 121.12, 121.15

Primary ExaminerI-I. Hampton Hunter 5 7 ABSTRACT An apparatus for producing preselected lengths of sewn fabric of the type used for belt loops on trousers or for entire belts in which sensing means and related circuitry are provided to detect and provide for elimination of defective material with the minimum amount of waste.

4 Claims, 4 Drawing Figures BACKGROUND OF THE INVENTION The present invention relates to an apparatus for producing fabric pieces of predetermined lengths or, more exactly, to produce both belt loops for trousers as well as entire belts. The trousers belt loops and the belts are generally made from material made up of fabric strips previously cut in lengths and then sewn together end to end to produce longer lengths of material. The lines of juncture between successive strips constitute imperfections and any strip of fabric containing such an imperfection must be discarded.

Apparatuses for making trouser belt loops are already well known, but their operation has not provided for the elimination ofjoints without the attendant wasting of substantial lengths of material. This was due to the fact that the cuts separating the material into individual lengths was effected by means of mechanical devices that operated at fixed intervals of time. As to the apparatuses for making belts, they are also well known, but these also presented significant problems in attempting to minimize waste generated by improperly timed cutting.

SUMMARY OF THE INVENTION To solve the technical problems inherent in existing apparatuses the apparatus of the invention is designed with an analyzer device positioned between the cutting device and the fault detector. Also there is a memorizer device connected with the analyzer and with the fault detector device; the analyzer device being designed to operate the cutting device when activated by preprogramming activation at intervals determined by information storage devices.

With this apparatus, it is possible to determine whether a detected fault will occur in the immediate piece to be cut from the raw stock or whether the fault will be in the next succeeding piece to be cut.

It is a principal object of this invention to provide a machine for producing both belt loops and belts, as desired.

Another object of this invention is to provide a belt and belt loop producing machine which includes means for detecting imperfections or faults in the material being worked on.

Other objects and advantages of this machine will be in part obvious and in part explained by the accompanying specification and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a schematic side elevation of the apparatus of this invention;

FIG. 2 is a partially sectional top elevation taken along the line IIIl of FIG. 1;

FIG. 3 is a partially sectional side elevation taken along the line IIIIII of FIG. 2; and

FIG. 4 is a schematic of the control circuit of the apparatus.

DETAILED DESCRIPTION OF THE INVENTION The apparatus of this invention includes a sewing machine (FIG. 1) to produce loops for trousers, belts and the like. Other types of fabric joining machines can be used in place ofa sewing machine if desired a sewing machine being described here only by way of example.

The said machine 10 usually comprises a base 11 on which the work is supported by a standard 12 which has on its upper end a supporting arm 13 for a reciprocating needle bar 14 which carries one or more needles 15 at a first work station. Located forwardly of the needle bar, in the sense of forward movement of the material, there is a presserfoot bar having on its lower end the usual presserfoot 17 which co-operates with the needles l5 and with the other well known sewing parts (not shown) to effect stitch formation. Auxiliary roller feeder 18 functions to keep the material stretched and to move it forwardly away from the areas of the needle 15 and presserfoot 17. It is formed by a bar 19 which is biased downwardly and is fitted with a first knurled roller 20. The roller 20 is mounted for rotation in forklike support 21 fixed to the said bar. There is also a second knurled roller 22 which is mounted on the base 11 under the roller 20. The second roller is similar to roller 20 and cooperates with roller 20 to effect advancement of the material. Finally on left end of base 11, as viewed in FIG. I, there is mounted at a second work station, a cutting device 23 which cuts the material coming out of the machine into several pieces.

The cutting device 23 includes an actuator 24, for example an electromagnet, a moveable blade 25 mounted on the end 26 of a lever having an arm 27 connected to actuator 24. A stationary blade 28 is attached to the base 11 in a position to cooperate with moveable blade 25 each time the moveable blade is moved by the actuator 24. Under the cutting device 23 there is a conveying-selecting device 29 having a first duct 30 which receives those completed pieces which have no faults and also having a second duct 31 through which those pieces go which are faulty. The closure of one duct and the opening of the other is effected by suitably controlling a moveable plate 32 which pivots about pin 33. The plate is pivoted against the biasing spring 34, by an actuator 35, which can be, for example an electromagnet having a moveable core 36 which is hinged to the plate 32. According to the position in which the said plate is, the duct 31 is open and therefore the sewn pieces received are rejected, or the duct 30 is open and the sewn pieces produced are accepted. A folder 37, which is optional depending upon the article being produced, completes the sewing machine which has been described. The folder 37 is used to fold over the edges of the fabric strips for subsequent sewing.

The apparatus includes also a control circuit for controlling the cutting device 23 and the conveyor-selector device 29. This control circuit is the system responsible for attaining the improved operating characteristics of this invention. In this apparatus usual devices for fixing the lengths of finished pieces are replaced by circuits that function only when a preselected power level, such as zero or one is achieved. By selecting the power level the apparatus can be adjusted to produce pieces of a length that can be used in the making of trouser loops or to produce pieces of a length so great as to be used in the making of belts. The material strip 38 is made up of shorter fabric strips which are sewn together at their ends so that the joints between strips can have overlapping material 39 (FIG. 1) or a gap 40 when the ends of two consecutive strips do not abut on the interior reinforcing tape. The joints are in these situations of thicknesses different from the rest of the strip and constitute defects.

Detection of these faults is done by detector device 41 (FIGS. 2 and 3) which is connected by means of a lever 42 and a peg 43 to the fork-like support 21 of the auxiliary roller feeders 18. In the section which are free of faults, the material 38 is of uniform thickness, but when the thickness of the strip is different, the roller is moved vertically by the variation in the thickness as soon as one of the said joints enters between the rollers 20 and 21. The vertical movement of the roller 20, and therefore of the fork-like support 21, is sensed by the device 41 which detects the faults by means of the lever 42. The lever 42 pivots about pin 44 which is attached to a support arm 45 mounted on the arm 18 of the sewing machine. The peg 43 is inserted into the fork-like end 46 of the lever 42 the other end of 47 of which is connected to sensor means comprised of, for example, a photocell 48 having a light receptor 49. The pivot point of the lever is such that a relatively small amount of movement of end 46 results in significantly greater movement of end 47. As a consequence, even the smallest variation in the thickness (vertical movement of roller 20) can activate the sensor means as the movement of end 47 causes the light of bulb 49 to pass to the photocell 48. To complete the fault detector device 41 there is also provided a support 50 for the sensor means which is mounted on an adjusting screw 51 on the upper part of base 52. By means of the adjusting screw 51, the fault detector device can be raised or lowered and therefore it can be used on materials of different thicknesses.

The apparatus of thy present invention can also be fitted with means to operate the cutting device 23 which are controlled by the length of the pieces to be produced. This length is calculated according to the amplitude and the number of the working cycles required by the driving part of the machine to obtain it. For example, in the case of a sewing machine, the main driving part is the needle bar and therefore the desired length is calculated according to the length of each of the stitches and the total number of stitches contained in the desired length. Therefore the activation of the cutting device 23, which is necessary to get a piece of the desired length from the material moving on the machine, depends only on the last cycle of the predetermined machine program. As the length of material depends on the completion of a predetermined set of the working cycles, the operation of the apparatus can be interrupted and resumed again without jeopardizing the correct carrying out of the programmed sequence. Detection of the cycles can for example be made of a feeler detector device 53 which can detect the presence of the needle bar 14 each time it passes in front of the device 53 and can send a pulse each time the bar 14 is detected to a pulse counter 54 (FIG. 4) with which device 53 is connected. In order to produce pieces of a desired length and to: (a) select the good ones from the defective ones, (.b) count only the good ones produced, (c) interrupt the sequential cutting immediately adjacent a fault and then restart the program adjacent the point where the defective portion has been removed, and (d) restore the normal working conditions at the end of the operations of elimination of the waste piece, the pulse counter 54 is connected with a set of adjustable pre-programming first, second and third comparator devices 55, 56 and 57 respectively.

These devices are capable of, respectively, predetermining the value of the X" length desired, which is expressed as the number of the cycles separating two normal cutting operations on a section of material free of faults; predetermining the value of the Y distance, which is also expressed by the number of cycles, and recognizing the distance between the cutting device 23 and the point where the faults have been detected by the roller 20. The Y distance is fixed but can vary from one apparatus to the other but is a necessary value since a section of the material inspected by the roller 20 reaches the cutting device 23 only after a Y" number of cycles have been carried out. Finally, the value of Z, also expressed by the number of the cycles, is the difference between the X and Y" values. Value Z is used as a comparison to establish immediately if a fault located by the roller 20 is in the section of material which is next to be cut or is in the next succeeding one. Each time the cutting device 23 effects a cut there is between the blade of the said cutting device and the roller 20 a part of the piece which has already been inspected and which has a length of the value Y. Therefore, if thy part inspected is free of faults, it is necessary only to complete a number of cycles equal to the value of Z in order to have another piece of X length. The detector device 53, besides being suitably connected with the pulse counter 54, is also directly connected with each of the adjustable preprogramming devices 55, 56 and 57. Therefore the same electric pulses transmitted by the detector device 53 to the pulse counter 54 are also transmitted to these pre-programming devices. As these electric pulses take on different power levels according with each cycle, the electric pulses which are sent by the pulse counter 54 to each pro-programming device raise to a power level equal to that emitted by the detector device 53 only when their sum total reaches the predetermined value. Therefore, each pre-programming device is activated by the combination of the two electric pulses at the entry of a power level equal to that required by the pre-programming. During the cycle device 55 memorizes that a part of the desired length has been produced; the pre-programming device 56 has memorized that that section has already completely overtaken the cutting device 23; the pre-programming device 57 has memorized that no fault has been detected in a whole section equal to Z cycles and therefore, that the remaining section equal to Y is certainly free offaults. At this time, the cutting device can be operated to produce a good piece.

As the two first adjustable pre-programming devices 55 and 56 are activated, they send their own electric pulse directly to an analyzer device 58 with which they are connected. The other adjustable pre-programming device 57, instead, sends its own electric pulses to the analyzer device 58 through a memory storage device 59 which is connected with the fault detector 41. In order to better understand the working of the apparatus of the present invention, some cases which can occur during the production of pieces are described below.

WORK WITHOUT FAULTS In the-case in which the material is free of defects, the memory device 59 keeps its normal state of rest as it is not pulsed by a signal from the fault detector 41. As a consequence the electric pulses emitted by the adjustable pro-programming devices 55 and 56 can help activate the analyzer device 58 when required. The activation of this device 58 causes immediately a variation in the power level of the electric pulse sent to a zero setting device 60 with which it is connected and which causes the immediate setting to zero of the pulse counter 54 by means of an electric pulse. This setting to zero is required to allow the immediate restarting of the counting from zero of the cycles even before the cycle successive to that which has caused the activation of the analyzer device 58 is completed. The conveyorselector device 29, which is also connected with the analyzer device 58, is not activated as the piece which is being cut is a good one. The conveyor-selector device 29 is required to be inactive to keep the plate 32 in a position permitting entry into duct 30. An electric pulse with a different power level is also sent to the cutting device 23 which therefore carries out the separation of the completed piece. The same electric pulse which causes the activation of the cutting device is sent, through the conveyor-selector device 29, to piece counter 61 suitable to count the good pieces produced. The counting of the good pieces is possible only if the conveyor-selector device 29 is inactive.

WORK WITH FAULTS In the case in which the material being worked shows faults, the roller is moved vertically thus triggering the fault detector device 41 and causing variation in the power level of the electric pulse sent to the memory device 59. If the fault is detected after a certain number of cycles has been counted up to a Z" value, the memorizer device 59 memorizes only the faulty condition of the material section being worked. It does not however end the working cycle because at that time a suitable section of material Y stitches long is already between the cutting device 23 and the roller 20 so that a good piece can be produced from the said material.

If the length of the detected and memorized fault, expressed in cycles, is shorter than the Y value, as soon as the separation cut of the piece already programmed has been completed, the memory device 59 influences the analyzer 58 so that the latter emits an electric pulse of such a power level as to activate the conveyorselector 29 which as a consequence moves the plate 32 to open waste duct 31. The activation of the same device 29 causes the interruption 'of the passage of the electric pulses to the piece numerator device 61. In this state, the analyzer device 58 does not pre-program the carrying out of the successive separation cut when the X" value has been reached. However, when enough stitches have been carried out to cover the Y" dis tance, the fault section will have passed cutting device 23 and can be eliminated. The waste section has a length equal to the Y value. The apparatus, in this case, has programmed the separation cut in a very special way by carrying out the cutting operation at a value lower than the X value, which had been predetermined. In the case in which the fault is detected when the number of cycles equal to the Z value has not yet been reached, that is, the detected value is in that section of the material from which the piece would have to be produced, the memorizer device 59, influenced by the fault detector device 41, immediately 6 sends an electric pulse to the detector device 53 of such a power level as to make it inactive. At the same time the same memorizer device 59 sends an electric pulse to the analyzer device 58 which, as a consequence, causes the activation of the zero setting device 60. The numerator device 54 is activated too and kept in this condition as long as the condition of the fault detector device 41 is operative. Another electric pulse is transmitted by the analyzer device 58 to the conveyorselector device 29 which arranges the plate 32 in such a position as to send to the waste container the defective piece. The activation of the conveyor-selector device 29 makes the piece counter 61 inactive in the same way as already explained. When roller 20 returns to its original position detector 41 is again inactive. The detector device 53 is again active and therefore resumes sending electric pulses to the pulse counter 54 starting from zero. At the same time, an electric pulse is transmitted by the memorizer device 59 to the analyzer de' vice 58 which arranges the control of the carrying out of the separation out only after a certain Y" number of cycles. Once the cutting operation is completed, the counting of the cycles starts again from zero, while the plate 32 returns to its original position under the action of a returning spring 34 as the electromagnet 35 deenergizes. The material section which has thus been eliminated has a total length equal to the sum total of the cycles actually carried out before the fault was found out plus the length of the fault itself. In this case too the apparatus has arranged the cutting so as to have the minimum material waste, that is, the cutting device 23 has been activated when the end part of the faulty section has overtaken the said cutting device and therefore obtained the separation just in back of the faulty part.

What is claimed is:

1. In an apparatus for producing fabric pieces of predetermined lengths in which the fabric is joined together at a first work station and cut into selected lengths at a second work station the combination comprising a. fault detector means mounted on said apparatus for vertical movement in response to variations in the thickness of the fabric, said means being located between the first and second work stations,

b. pulse emitting means operatively associated with the fabric joining means to emit a pulse for every working cycle of the fabric joining means,

c. pulse counting means connected to said pulse emitting means,

d. first, second and third comparator means connected to said pulse emitting means and to said pulse counting means to receive pulses therefrom, said pulse comparator means being preprogrammable to require the combined pulses received from said pulse emitting means and from said pulse counting means to reach a predetermined power level before being activated,

e. memory storage means connected to receive input pulses from said fault detector means (a) and from said third comparator means (d) and connected to deliver an output pulse to said pulse emitting means (b),

f. analyzer means connected to receive output pulses from said first and second comparator means (d) and from said memory storage means (e),

g. means connected to said analyzer, means (f) to reset said pulse counting means (0), and

h. cutting means connected to said anayzer means (f) to effect cutting of the fabric upon receiving the appropriate signal.

2. An apparatus as defined in claim 1 wherein there is conveyor-selector means connected to said analyzer means to remove good pieces of fabric and defective pieces of fabric to different sites.

3. An apparatus as defined in claim 2 wherein counting means is connected to said conveyor means to count the number of good pieces of fabric produced.

4. In an apparatus for producing fabric pieces of predetermined length in which the fabric is joined together at a first work station and cut into selected lengths at a second work station the combination comprising a. fault detector means mounted on said apparatus for producing a pulse upon movement in response to variations in the thickness of the fabric,

b. cutting means to cut the fabric into lengths of predetermined size,

0. pulse emitting means operatively associated with the fabric joining means to emit a pulse for every working cycle of the fabric joining means, and

d. means connected to receive the pulses from said fault detector means and from said pulse emitting means and to said cutting means to cause operation of said cutting means in response to the length of fabric produced and in response to the presence of faults in the fabric. 

1. In an apparatus for producing fabric pieces of predetermined lengths in which the fabric is joined together at a first work station and cut into selected lengths at a second work station the combination comprising a. fault detector means mounted on said apparatus for vertical movement in response to variations in the thicknesS of the fabric, said means being located between the first and second work stations, b. pulse emitting means operatively associated with the fabric joining means to emit a pulse for every working cycle of the fabric joining means, c. pulse counting means connected to said pulse emitting means, d. first, second and third comparator means connected to said pulse emitting means and to said pulse counting means to receive pulses therefrom, said pulse comparator means being pre-programmable to require the combined pulses received from said pulse emitting means and from said pulse counting means to reach a predetermined power level before being activated, e. memory storage means connected to receive input pulses from said fault detector means (a) and from said third comparator means (d) and connected to deliver an output pulse to said pulse emitting means (b), f. analyzer means connected to receive output pulses from said first and second comparator means (d) and from said memory storage means (e), g. means connected to said analyzer, means (f) to reset said pulse counting means (c), and h. cutting means connected to said anayzer means (f) to effect cutting of the fabric upon receiving the appropriate signal.
 2. An apparatus as defined in claim 1 wherein there is conveyor-selector means connected to said analyzer means to remove good pieces of fabric and defective pieces of fabric to different sites.
 3. An apparatus as defined in claim 2 wherein counting means is connected to said conveyor means to count the number of good pieces of fabric produced.
 4. In an apparatus for producing fabric pieces of predetermined length in which the fabric is joined together at a first work station and cut into selected lengths at a second work station the combination comprising a. fault detector means mounted on said apparatus for producing a pulse upon movement in response to variations in the thickness of the fabric, b. cutting means to cut the fabric into lengths of predetermined size, c. pulse emitting means operatively associated with the fabric joining means to emit a pulse for every working cycle of the fabric joining means, and d. means connected to receive the pulses from said fault detector means and from said pulse emitting means and to said cutting means to cause operation of said cutting means in response to the length of fabric produced and in response to the presence of faults in the fabric. 